On 05/20/2014 09:03 AM, Sasha Levin wrote: > On 05/20/2014 07:04 AM, Peter Zijlstra wrote: >> > On Mon, May 19, 2014 at 10:05:31PM -0400, Sasha Levin wrote: >>> >> ping? It seems to be easy enough to reproduce on -next, I'd be happy to >>> >> try >>> >> debug patches/fixes. >> > >> > Does this fuzzing you do also include hotplug? If so, does disabling >> > that make this problem go away? >> > > There were no hotplug operations going on when this happens, so it seems > unrelated.
I've added a small test: diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 927fa33..b5e11c7 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1154,6 +1156,7 @@ int migrate_swap(struct task_struct *cur, struct task_struct *p) goto out; trace_sched_swap_numa(cur, arg.src_cpu, p, arg.dst_cpu); + BUG_ON(cur == p); ret = stop_two_cpus(arg.dst_cpu, arg.src_cpu, migrate_swap_stop, &arg); out: Which seems to get hit. This sounds like a race with task moving to other cpu maybe? Thanks, Sasha -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/